1. Field of the Invention
The present invention relates to surgical instruments and more particularly to an improved orthopedic surgical instrument that is used to remove or insert an elongated intramedullary rod from the intramedullary canal of a patient's bone. More particularly the present invention relates to an improved quick release handle that forms a quick release connection with the top of an intramedullary rod that has been surgically implanted. Even more particularly the present invention relates to an improved quick release handle and an accompanying separate nail puller element that threadably attaches to the top of the intramedullary rod. At its opposite end the nail puller element releasably attaches to the distal end portion of the handle. Quick connect and quick disconnect with the nail puller is achieved using a plurality of circumferentially spaced ball bearings on the handle that engage an annular groove on the nail puller.
2. General Background
Elongated intramedullary rods are commonly used to repair bone fractures of a patient's long bone (eg. femur). These intramedullary rods are often used in combination with bone screws. For example, U.S. Pat. No. 5,167,663 issued to Brumfield describes an intramedullary rod having diagonal extending openings at its proximal end portion and transversely extending openings at its distal end portion. In the Brumfield patent the diagonal openings are directed towards the patient's acetabulum. Transverse are provided at the distal end of the rod, to be occupied by transverse bone screws. U.S. Pat. No. 5,167,663 is hereby incorporated herein for reference.
Intramedullary nails have been removed with instruments that can removably attach to the proximal end of the nail. An example of such a nail and a tool for removing that nail is seen in U.S. Pat. No. 4,169,470 entitled "Surgical Nail for Use in Setting Bone Fractures, and Tool for Emplacing Same" issued to Josef Ender and Hans G. Ender. The Ender patent shows an intramedullary nail having a specially shaped end portion that excepts a tool. The tool resembles a pair pliers having a nose portion that moves into a recess for gripping the nail so that the nail can be withdrawn or angularly adjusted when the connection is made between the tool and the nail. Other embodiments show other connections between the removal tool and the top of the nail.
Prior to the insertion of a femoral prothesis, a rasp tool is often used to shape the patient's intramedullary canal. It has been known in the art to manipulate these rasps using handles. These rasp handles have been equipped with a quick connect coupling to quickly connect/disconnect with the rasp. An example of such a rasp and handle assembly is shown U.S. Pat. No. 4,306,550 entitled "Combination Including Femoral Rasp and Calcar Facing Reamer", naming Mark Forte as inventor. The Forte patent discloses a combination of tools and methods used to prepare a socket in a femur for receiving a femoral prothesis including a rasp having a cutting portion and a pilot post portion, a handle assembly with a chuck for releasably engaging the pilot post portion to facilitate working the rasp into a femur, and a cutter device adapted to be journaled on the pilot post and power driven to surface the calcar adjacent the socket. After a socket is formed in the femur by use of a rasp and handle assembly, the rasp is left in the socket. The handle assembly is then removed, and the cutter is journaled over the pilot post and rotated by a drive apparatus.
The Kenna patent 4,583,270 entitled "Rasp Handle" discloses a rasp handle that has an elongated body portion with a pistol type grip extending therefrom and with a rasp retaining structure at its opposite. The structure includes a fixed jaw and a slide jaw constructed and arranged for sliding movement relative to the fixed jaw between a forward closed locking position where a rasp is locked between the jaws and a rearward open rasp receiving and releasing position. The lever is connected to shift the slide jaw between its open and closed positions. A pivot interconnects the lever and the slide jaw so that the lever is free to move between a locked position adjacent the body portion and an unlocked jaw manipulating position away from the body portion. Another rasp tool that includes a handle is disclosed in Walker's patent 4,587,964 entitled "Rasp Tool". The Walker patent includes a handle and a cutter as part of the rasp tool. The handle carries a releasable locking assembly to couple the cutter to the handle and the releasable locking assemble is compactly arranged at one end of the handle via transversely extending flange which also acts as spacer between the releasable locking assembly and the roughened outer surface of the cutter.
In the Chiarizzio patent 4,601,289 there is disclosed a femoral trial prothesis/rasp assembly used in hip implant surgery. The assembly includes a handle that grips the combination trial prothesis/rasp in a secure manner by clamping over and locking on to a post on the trial prothesis/rasp which later serves as a mounting piece for a femoral prothesis head used in trial reductions.
A coupling arrangement for selectably coupling and uncoupling a handle and the blade of a surgical instrument such as a broach is disclosed in the Keller patent 4,765,328.
The Webb patent 4,921,493 discloses a rasp tool that comprises a handle and a cutter. The rasp tool carries a releasable locking assembly to couple the cutter to the handle. The releasable locking assembly is compactly arranged at the distal end of the handle and the mating proximal end of the cutter. The assembly includes a first interconnecting means for opposing longitudinal separation between the handle and the cutter, and a second inter connecting means for opposing lateral motion between the cutter and the handle. The releasable locking assembly is set to manually control attaching and detaching the cutter to the handle.
A releasable orthopedic broach handle apparatus is the subject of U.S. Pat. No. 4,990,149 issued to Thomas W. Fallin and naming Richards Medical Company as assignee. The Fallin patent discloses a modular broach handle for use with a broach having a tapered configuration beginning at a wider upper end and tapering to a smaller lower end. An elongated handle body portion has a longitudinal axis, with one end portion of the handle body defining a connection end portion for attaching a broach thereto at the wider upper end portion of the broach. A slot extends a distance along the handle terminating at one end thereof adjacent a connection end portion with the handle body. A socket communicating with the slide is formed at the connection end portion of the handle body, the socket having an open end portion receptive of an attachment post on the wide end portion of the broach. A spring loaded slider bar is disposed within the slot for sliding movement therewith and with respect to the handle between engaged and disengaged positions, and includes an end portion that extends into the socket when in an engaged position to form a connection with the post. Slider bar and handle socket form a releasable locking mechanism between the post of the broach and the handle that is perfected upon assembly by pushing the post onto the socket, without manipulation of the slider bar.
U.S. Pat. No. 5,089,003 entitled "Rasp Tool Including Detachable Handle Member" discloses a rasp tool, handle member, and cutter member and a releasing locking mechanism for selectively coupling the handle and the cutter member. The locking mechanism includes a locking post on cutting member and a corresponding post receiving bore in the handle member. A spring-biased locking key is disposed within a guide bore that intersects the post receiving bore such that the locking key extends partially into the post receiving bore. As the locking post is actually introduced into the post receiving bore, the locking post contacts the locking key and causes it to retract until the locking post is fully received within the bore at which point the spring-biased locking key engages a transverse notch in the locking post thereby preventing actual removal of the post from the bore. The locking key is disengaged from the locking post by a trigger coupled to the locking key.
The Averill patent 5,089,004 provides a prosthetic implant procedure and femoral broach that includes a handle that forms a connection with the broach.
A locking surgical tool handle system is disclosed in U.S. Pat. No. 5,190,549, issued to Gary Miller and Matthew Lyons. The '549 patent discloses a surgical tool handle that has an elongated body portion with a pistol type grip. The front end of handle body has a tool retaining structure comprising a contoured engagement face and a moveable tension bar within an engagement end. Projections on the engagement end of the tension bar fit within a receiving channel of a surgical tool such as a broach or rasp. A locking mechanism is provided within the handle body and is implemented with pivotal links attached to the tension bar. The locking mechanism has an unlocked position in which the engagement end of the tension bar is spaced away from the engagement face of the handle body and an over center locked position which the engagement end of the tension bar is retracted toward the handle body. When the tool handle is placed in the locked position the engagement end of the tension bar pulls the attached tool into tight contact with the engagement face of the handle body.